Primary 4 Basic Science and Technology Flashcards: Meaning, Types and Uses of Simple Machines

Question 1

What is a simple machine?

Accepted Answer

a device that makes work easier

Question 2

What is a lever?

Accepted Answer

a rigid bar that turns around a fixed point

Question 3

The fixed turning point of a lever is called the ____.

Accepted Answer

fulcrum

Question 4

The force applied to a lever is called the ____.

Accepted Answer

effort

Question 5

The object moved by a lever is called the ____.

Accepted Answer

load

Question 6

In a first-class lever, the ____ lies between effort and load.

Accepted Answer

fulcrum

Question 7

In a second-class lever, the ____ lies between fulcrum and effort.

Accepted Answer

load

Question 8

In a third-class lever, the ____ lies between fulcrum and load.

Accepted Answer

effort

Question 9

Which is a first-class lever: scissors, wheelbarrow, nutcracker, or bottle opener?

Accepted Answer

scissors

Question 10

Which is a second-class lever: wheelbarrow, seesaw, scissors, or tweezers?

Accepted Answer

wheelbarrow

Question 11

Which is a third-class lever: tweezers, wheelbarrow, bottle opener, or seesaw?

Accepted Answer

tweezers

Question 12

A bottle opener makes work easier by acting as a ____.

Accepted Answer

lever

Question 13

What is a complex machine?

Accepted Answer

a machine made of two or more simple machines

Question 14

Which is NOT a simple machine: lever, pulley, wheel and axle, or car?

Accepted Answer

car

Question 15

The main reason machines are useful is that they ____.

Accepted Answer

reduce the effort needed to do work

Question 16

A ramp is an example of an ____.

Accepted Answer

inclined plane

Question 17

A pulley helps to lift a load using a ____.

Accepted Answer

rope running over a wheel

Question 18

The correct position for a fulcrum is at the point where the lever ____.

Accepted Answer

turns

Question 19

Why does a longer lever arm often make lifting easier?

Accepted Answer

it gives greater turning effect

Question 20

What should be checked before using a homemade lever?

Accepted Answer

that its parts are firm and safe

Strong work.